FREEDOM251

Freedom251 › Email Finder Software

Email Sleuth

Free plan LinuxMacWindows

Visit Email Sleuth Alternatives

Email Sleuth's own site

What Email Sleuth is

Email Sleuth is a free, open-source Rust application for discovering and checking professional email addresses from a person’s name and company domain. A single-contact lookup uses those two fields, while batch mode reads a JSON array containing first name, last name, and domain values and can save results to a JSON file. Basic, enhanced, and comprehensive verification modes combine DNS and SMTP checks; enhanced adds API checks, and comprehensive adds a headless browser. Results may include a best-guess address, confidence score, candidate addresses, verification status, methods used, and a verification log. The tool can generate plausible candidates and scrape company websites for addresses. Its command-line interface can print a simplified summary or save detailed output. It runs on Linux, macOS, and Windows, is MIT licensed, and is intended for contact enrichment, cold email, lead generation, and email verification. SMTP checks need outbound port 25 access, which many ISPs block.

Who it suits

It suits people finding or verifying business contacts when they know a person’s name and company domain. Teams handling larger contact lists can use JSON batch processing.

What it does well

  • Free and open source
  • Single and batch lookups
  • Three verification modes
  • JSON output options
  • Linux, macOS, and Windows support

What to know first

  • SMTP checks require outbound port 25
  • Many ISPs block port 25
  • API providers are not named

Limits

SMTP verification depends on outbound port 25, which many ISPs block. Enhanced and comprehensive modes add API checks or a headless browser, respectively.

Getting started

  1. Open the Email Sleuth GitHub repository
  2. Install it with the unified installer or download a platform binary
  3. Install ChromeDriver through the installer for browser-based verification
  4. Provide a contact name and company domain for a single lookup
  5. Or supply a JSON array with first name, last name, and domain fields
  6. Choose basic, enhanced, or comprehensive verification
  7. Print a summary or save detailed results to a JSON file

Verdict

Email Sleuth combines contact discovery, verification, and batch JSON handling in a cross-platform command-line tool. Port 25 restrictions may require enhanced or comprehensive verification, a suitable server, or another permitted connection.

Questions

Is Email Sleuth free?

Yes. It is free and open source, and the repository identifies an MIT license.

Which platforms does it support?

Email Sleuth supports Linux, macOS, and Windows.

Can it process contacts in bulk?

Yes. Batch mode reads a JSON array with first name, last name, and domain fields and can write results to JSON.

What verification methods are available?

Basic uses DNS and SMTP. Enhanced adds API checks, while comprehensive also adds a headless browser.

What can its results contain?

Results may include a best-guess email, confidence score, candidate emails, verification status, methods used, and a verification log.

Facts from Email Sleuth's own pages

Batch processing
Batch mode accepts a JSON array of contacts with first name, last name, and domain fields. · github.com, 11 Oct 2026
Browser verification
The installer can install ChromeDriver for enhanced verification, and the README describes managing its service from the CLI. · github.com, 11 Oct 2026
Email discovery
It can generate plausible email candidates and scrape company websites for addresses. · github.com, 11 Oct 2026
Installation
The maker provides a setup script, manual binary downloads, and instructions to build from source; the README describes Windows, macOS, and Linux binaries. · github.com, 11 Oct 2026
Integrations
The README mentions API-based checks but does not name specific API providers or integrations. · github.com, 11 Oct 2026
Intended use
Repository topics include cold email, contact enrichment, email verification, lead generation, and open source. · github.com, 4 Oct 2026
Intended users
The README describes finding valid email addresses for business contacts when the user knows the contact’s name and company domain. · github.com, 11 Oct 2026
License
The repository lists an MIT License. · github.com, 11 Oct 2026
Lookup
A single-contact lookup takes a person’s name and a company domain. · github.com, 4 Oct 2026
Network requirement
SMTP verification requires outbound access to port 25, which the README says many ISPs block. · github.com, 11 Oct 2026
Output options
The CLI can print a simplified summary or save detailed results to a JSON file. · github.com, 11 Oct 2026
Purpose
Email Sleuth is a Rust application that discovers and verifies professional email addresses from contact names and company domains. · github.com, 11 Oct 2026
Results
Results can include candidate addresses, confidence scores, verification status, methods used, and verification logs. · github.com, 11 Oct 2026
SMTP requirement
SMTP verification requires outbound access to port 25, which the README says many ISPs block. · github.com, 4 Oct 2026
Support
The repository provides an Issues page for questions and reports; the README does not state a support service or response commitment. · github.com, 11 Oct 2026
Verification methods
Its three modes use DNS and SMTP, add API checks in enhanced mode, and add a headless browser in comprehensive mode. · github.com, 4 Oct 2026
Verification modes
It offers basic, enhanced, and comprehensive verification modes using combinations of DNS, SMTP, API checks, and a headless browser. · github.com, 11 Oct 2026
Workarounds
For blocked SMTP access, the README suggests enhanced or comprehensive modes, a cloud server, or a VPN that allows port 25 traffic. · github.com, 11 Oct 2026

Where Email Sleuth stands on Freedom251

Look at these too